Surface-contact railway.



No. 677,966. Patenfed July 9, l90l.

P. FARNSWORTH. SURFACE CONTACT RAILWAY.

J (Applicatimi med Km. 5, 1901. (No Modal.)

rm: ppnms Penn: :0, vmrraumo. wmmoYom-m an UNITED STATES PATENT OFFICE.

PHILIP FARNSIVORTH, OF SCHENEGTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, OF NEW' YORK.

SURFACE-CONTACT RAILWAY.

SPECIFIGATION formingpart of Letters Patent No. 677,966, dated July 9, 1901.

Application filed March 5, 1901.

electromagnetic switches which are progress-' ively energized as' the car proceeds on its way.

The invention consists in means whereby the low-potential auxiliary source on the car can be utilized to energize initially one of the electromagnetic switches while protecting the auxiliary source from the consequent flow of line-current and at the same time automatically reduciug the ampere-turns in the magnet-coils after they have actuated theirswitches.

The invention also consists in means for cutting out the resistance which is employed to permit the use of a low-potential auxiliary source in such manner that the switchcoils will be constantly supplied with current without shunting the, resistancefrom the circuit of the auxiliary source.

In the patent to Orehore the switch-coils are shown connected in shunt to the return around the car-motors. An auxiliary source of current on the car is connected in shunt to the return around the switch-coils, and a resistance on the car is connected between the motor-circuit on one side and the auxiliary source and the switch-coils on the other to serve a double purpose. The first is to protect the auxiliary source from the line-current, which flows to the auxiliary source as soon as the electromagnetic switch is closed and before the motorman can cut the auxiliary source out of circuit. The second is to reduce the ampere-turns in the switch-coils after they have actuated their switches. The auxiliary source is shown as a secondary battery, and the resistance was useful also in charging the battery. This resistance, how- Serial No. 49,681. (No model.)

them it is evident that in this arrangement there is a considerable useless expenditure of energy.

Several ways have been suggested for antomatically reducing the ampere-turns in the switch-coils after they have actuated their switches; but in each of such cases it has been necessary either to employ a high-potential auxiliary source on the car or else leave continuously in circuit the resistance which protects the auxiliary source from the line-current.

One method'was to insert a resistance in series with each coil after it had actuated its switch, and while this method could be employed as an element of an em bodiment of the present invention, nevertheless in that case the resistance which protected the auxiliary source was always in series with it, so that itwas essential to have the latter at a high potential in order that the electromagnets could be energized through the resistance. Another method suggested was to out out part of the switch-energizing coil after it had actuated its switch, and yet another was first to connect two coils in parallel to actuate the switch and then connect them in series to hold the switch closed. In this method a short circuit to ground occurred in changing the coils from parallel to series, and hence it was necessary to maintain continually in circuit the resistance which protected the auxiliary source. I have adopted a'modified form of the last method as preferable for use as an element of the present invention; but other methods might be utilized in this connection.

In accordance with this invention the auxiliary source is to be connected directly with the switch-coils to energize the latter initially to connect a conductor-section with the feeder.

The resistance on the car is connected between the auxiliary source and the switch-coils in shunt from the motor-circuit. Thus a lowpotential source can be employed, as there is I no resistance interposed between the auxiliary source and the switch-coils, while at the same time the resistance serves to protect the auxiliary source from the line-current after an electromagnetic switch has been closed and before the motorman can cut the auxiliary source out of circuit. Up to this point the arrangement is the same as that shown in the patent to Crehore above noted. There is now added, however, means for automatically reducing the ampere-turns in the switch-coils after they have actuated their switches. This means may be entirely independent of the resistance on the car, so that one reason for the retention in circuit of said resistance is removed. Furthermore, any desired suitable means can be employed for this purpose which will be operative as an element of the combination. The parallel-series method is used for this purpose and is so modified that the retention of the car resistance is not required. There is provided a further means for shortcircuiting the car resistance, so that it is cut out of circuit with the collecting device and current flows direct from the motor-circuit to the switch-coils, which have by this time closed the switch and have their am pere-turns reduced. This resistance is short-circuited gradually, since sufficient current must be supplied to the switch-coils to hold the switch closed, and if the terminals of the resistance are bridged while the auxiliary source is in circuit the function of the resistance will be defeated. In the meantime, however, the resistance on the car is left in circuit with the auxiliary source in order to prevent a short circuit through the latter, and in case the auxiliary source is a battery to permit its being charged from the motor-circuit. Finally after the resistance is shunted from the circuit of the collecting device, but in series with the auxiliary source, current being supplied to the switch-coils from the motor-circuit, the auxiliary source can be cut out.

The illustration is a working drawing of the electric circuits, showing in a somewhat diagrammatic manner the apparatus which is employed. It is contemplated that apparatus now well known in this art will be employed, which may be modified by the constructor in any desired manner to execute the invention, as described hereinafter.

The conductor-sections are represented by the letters E, E and E and P, P and P and are engaged by the collecting devices N and H, carried by the car. All the apparatus above these conductor-sections is carried by the car and all that shown below the conductor'sections is intended to be located in any suitable place along the roadway. Below the respective conductor-sections are shown three electromagnetic switches, the coils of which are connected in shunts to the return around the car-motors M. The conductor-sections P, P and P are the powersections and are adapted to be connected to the feeder F by electromagnetically-actuated switches to, 10 and 10 The collecting device H engages these power-sections P, P and P to convey current through the carcontroller K, any suitable resistance r, and

the car-motors M to the return R. The return may be either the track-rails or any suitable insulated circuit. The energizingcoils for the switches 20, 10 and 20 are connected to the motor-circuit from the return R through the conductor-sections E, E and E, which are engaged by the collecting device N.

In the position shown the car is in normal operation in either direction, with the collecting device engaging two successive sec tions, whereby the switches W and W are held closed, so that current is being supplied 'to the car through the two shoes of the collector H in parallel. The switches are held closed bycurrent flowing from the motorcircuit in shunt to the resistance r through the contact 4, the switch-piece K, the col-- lector N, the two successive switch-en ergizing conductor-sections E and E and the coils O B and O B to the return R. In their closed positions the subdivided coil portions 0 and B are connected in series by the switch-contact 6, which bridges the fixed contacts 9 and 11, whereby the ampere-turns are substantially one-half of the number employed in moving the switches NV and W to their closed positions. When held by gravity in their open positions, the switches, as in the case of the switch W are adapted to be quickly closed by current flowing-through the coils O and B in parallel to the return R. The switch-piece 6 connects the coil 0 to the return through the fixed contacts 9 and 10, and the switch-piece 5 connects the coil B to the return through the fixed contacts 7 and 8. hen the collecting devices engage the sections E and P the switch will be actuated with these coils in parallel, and as the switch moves toward its closed position the switchpiece 5 will move off from the contacts 7 and 8 and the coil B will be temporarily cut out of circuit. As the switch W moves farther toward its closed position, the switch-piece 6 will leave the fixed contact 10 and will engage the fixed contact 11, so that current will flow through the coil 0 the fixed contact 9, switch-piece 6, fixed contact 11, fixed contact 8, and the coil B to the return, as is the case with the switches IV and WV as shown.

During the normal operation of the car the resistance r is shunted from the circuit of the collector N and the successive switches W, IN, and V will be first actuated with full current with the divided coils in multiple, and then these coil portions will be automatically cut in series to reduce the ampereturns to a degree just sufficient to hold the switches closed.

Then the car is stationary and the linecurrent has been lost for any reason, the switch-piece K is moved ina direction opposite to the movement of the hands of a clock to engage the cont-act 1. This movement carries the switch-piece K which is suit-ably insulated from the switch-piece K, into engagement with the fixed contact 12, so that coils.

the auxiliary source U, which may be a battery or any other suitable generator, is connected through the contact 1, switch-piece K, and the collecting device N directly through the switch-coils to ground. Asthere is no resistance interposed between the battery and the switch-coils the battery may be of quite low potential, and therefore maybe composed of a small number of cells occupyinga minimum amount of space and requiring comparatively little attention. The closing of this circuit will energize the switch-coils to close the switches, cutting the divided portions in series to hold the switch closed with reduced ampere turns. The switch K is now revolved clockwise to successively engage the contacts 2, 3, and 4,. thereby gradually short-circuiting the resistance with respect to the collecting device N, but leaving the entire resistance in series with the battery U to protect the latter from the linecurrent flowing in the motor-circuit. When the battery is used as the auxiliary source,

the switch K might be held for a short interval on the contact 3 in order to permit the battery to be charged through the resistance 7'. As the switch-piece K leaves the contact 3 the switch-piece K leaves the contact 12, thereby cutting the battery out of circuit. The resistance 1" has thus served its purpose of preventing a short circuit through the auxiliary source and as a means for charging the battery and is now entirely cut out of circuit andis kept out during the normal operation of the car, as it is not needed in series with the switch-magnets, since separate means is provided for automatically reducing the current flowing through them after they have actuated their switches.

It will be noted that current must be continually supplied to the switch-coils either from the battery or the motor-circuit, or both, in order to prevent the switches from opening after they have once been closed. Hence there must be no open circuit between the time that the switch-piece K leaves the contact 1, when the batteryis connected directly with the switch-coils, and the time that the switch-piece K engages the contact 4, thus completely shunting the resistance 1" from the circuit of the collector N and connecting the motor-circuit directly with the switch- The battery connection direct with the switch-coils should not be broken until a part of the resistance r is cut out, for if the feederswitches W could be held closed with the entire resistance r in series with their coils these coils would normally receive a current when the resistance r was entirely out out which would be needlessly large for the purpose of holding them closed. It the switchpiece K should be constructed to bridge the contacts 1 and 4 when the battery was in circuit, there would be a short circuit through the battery and the entire utility of the resistance r would be defeated. Thus it is seen that the gradual shunting of the resistance r from the collector-circuit provides a means for continually supplying current to the switch coils, prevents a short circuit through the battery, and the switches need not be adapted to be held closed by a smaller current at this stage than during the normal progress of the car. The successive portions of the resistance r, which are cut in between the battery and the switch-coils to reduce the flowing through them, the current-supply.

through the collector N is exactly the same whether the switch-piece K is in engagement with the contact 1 or the contact 4.

The switch K and K is shown separate from the controller K in order to more clearly illustrate the invention; but its contacts may be added to the cylinder of the controller K in the same manner in which any extra contacts are usually added to a controller when it is desired to-have the latter perform extra duty. The controller K can be operated to supply current to the motors M as soon as the feeder-switch is closed, and hence the first operating-contact on the controller can be located at any suitable point after the contact K closes the battery-circuit in the case where the switch K K with its contacts, is made a component part of the controller.

What I claim as new, and desire to secure by Letters Patent of the United States, is-

1. In an electric railway, the combination with the feeder, of conductor-sections, electromagnetic switches for connecting the feeder with the conductor-sections, the magnet-coils being connected to the return in shunt to the car-motors through a suitable collecting device, means for reducing the ampere-turns in the magnet-coils after they have actuated their switches, an auxiliary source of current on the car, which is adapted to be connected with the switch-coils, a resistance on the car which is adapted to form a portion of said shunt-circuit, the collecting device being connected to a point between said auxiliary source and said resistance, and means for rendering said resistance inoperative in the circuit of the collecting device.

2. In an electric railway, the combination with the feeder, of conductor-sections, electromagnetic switches, the magnet-coils being subdivided, the subdivided portions being connected to the return in shunt to the carmotors by a suitable collecting device and normally connected in parallel with respect to each other; means for connecting the subdivided portions in series when they have actuated their switches, an auxiliary source of &

current on the car which is adapted to be connected with the switch-coils through the collecting device, a resistance on the car which is adapted to form a portion of said shunt-circuit, the collecting device being connected to a point between said auxiliary source and said resistance, and means for renderin g the said resistance inoperative with respect to the circuit through the collecting device.

3. In an electric railway, the combination with the feeder, of conductor-sections, electromagnetic switches, the magnet-coils being subdivided, the subdivided portions being connected to the return in shunt to the carmotors by a suitable collecting device and normally connected in parallel with respect to each other, means for connecting the subdivided portions in series when they have actuated their switches, an auxiliary source of current on the car, which is adapted to be connected with the switch-coils through the collecting device, a resistance on the car which is adapted to form a portion of said shunt-circuit, the switch-coils being connected through the collecting device to a point between said auxiliary source and said resistance, and a switch for short-circuiting said resistance with respect to the circuit through the collecting device.

4. An electro1nagnet,the energizing-circuit of which is divided, in combination with a switching device controlled by the energizing-circuit, which normally connects the divided portions of said circuit in parallel, cuts out one divided portion when the magnet is energized, and then connects both portions in series with each other.

5. The combination with an electricallypropelled car, of an auxiliary source of current carried thereby, a resistance connected in shunt to the motor-circuit, a collecting device, and a switch which connects the collecting device directly between the auxiliary source and the resistance, and then gradu- 5 ally cuts the resistance out of the circuit through the collecting device, thus leaving the resistance in series with the auxiliary source.

6. The combination with an electricallypropelled car, of an auxiliary source of current carried thereby, a resistance connected in shunt to the motor-circuit, a collecting device, and a switch which connects the collecting device directly between the auxiliary source and the resistance, then gradually cuts the resistance out of the circuit through the collecting device, leaving the resistance in series with the auxiliary source, and finally cuts the auxiliary source out of circuit.

7. In a sectional-conductor railway, the combination with an auxiliary source of current carried by the car, a resistance in shunt to the return around the car-motors, a collecting device carried by the car and connected between the auxiliary source and the resistance, and means for changing the connection of the collecting device from the point between the resistance and auxiliary source to a direct connection with the motor-circuit.

8. The combination with an electricallypropelled car, of an auxiliary source of current, a resistance connected in shunt to the motor-circuit, a collecting device normally connected in shunt to the motor-circuit, and a switch which connects the auxiliary source directly to the collecting device, and connects the collecting device through the resistance to the motor-circuit, and gradually cuts the resistance out of the circuit through the collecting device, without cutting the resistance out of circuit with the auxiliary source.

In witness whereof I have hereunto set my hand this 28th day of February, 1901.

PHILIP FARNSWORTH.

l/Vitnesses:

BENJAMIN B. HULL, MARGARET E. WooLLnY. 

